Results & DiscussionCharacterization of targeted ?-tocopherol-PLGA functionalized 5-FU(?-T-FU-PLGA) & non-targeted 5-FU NanoformulationsThe surface conjugation of ?-tocopherol as atargeted moiety on 5-FU-PLGA nanoparticles eventually increased in averageparticle size ranges from 145 nm to 160 nm as the non-targeted nanoparticles formulation having the negative surfacecharge about -17mV and increased in ?-tocopherol functionalized?-tocopherol-FU-PLGA nanoformulation as shown in Figure 2A & 2B. The PDI,particle size and zeta potential were summarized in Table 1. SEM of the?-tocopherol-FU-PLGA/5-FU-PLGA nanoformulation confirmed that as sphericalshape of the nanoparticles with the easysurface as shown in Figure 3.In-vitro drug release system and entrapment efficiencyTo study the in vitro release system and entrapmentefficiency of 5-FU-PLGA/?-tocopherol-FU-PLGA nanoparticles, the standard calibration curve of the 5-FU solution was a linear regression in the ranges from 0.1 to 10 µg/ml, a straightline was found between 5-FU concentration (µg/ml) and absorbance (nm) throughthe UV spectrophotometer at absorption maxima 267 nm as shown in graph, Figure4. In-vitro drug release of nanoparticles also depends upon particlesize, when size is less, the surface areaof nanoparticles increases and more surface area come in contact with the medium, resulting in a faster release.
The cumulative in-vitro drug release at pH 7.4& pH 4.5, to identify the pH susceptible difference in a 5-FU release from the nanoparticulate system and the entrapment efficiency of 5-FU loadedin ?-tocopherol-FU-PLGA/5-FU-PLGA nanoparticles were 68% and 63% respectivelyfor both the nanoformulations.
The total amount of commutative in vitro drugrelease at the pH 4.5 was increased 70 %at the time range of up to 160 hours the results of 5-FU-PLGA nanoparticlesshowing steady state release approximately at the time 140 to 160 hours and 63%in ?-tocopherol-FU-PLGA nanoparticles which was having targeted moiety. In vitrodrugs release data for ?-tocopherol-FU-PLGA & 5-FU-PLGA nanoparticles in pH7.4 showed rapid releases at time range 40 to 60 hours about 35% to 60% &25% to 50% respectively, which was followed by the cumulative drug release upto 160 hours about 85% & 82% respectively. The slope of the graph for in-vitrorelease system for the ?-tocopherol-FU-PLGA & 5-FU-PLGA nanoparticles atdifferent pH (7.4 & 4.5) ranges confirm the optimum drug release atdifferent time interval up to 160 hours, shown in Figure 5, and the releasekinetic at the pH 7.
4 & 4.5 confirm that cumulative drug release stronglyinfluence the pH of the dissolution solution. The data for drug releasesummarized at a different time intervalin Table 2.Cell CultureCytotoxicity of ?-Tocopherol-FU-PLGA/5-FU-PLGA nanoparticles indose-time dependent on SCC-15Cytotoxicity study, in reference to dose and time-dependent, 5-FU-PLGA/?-tocopherol-FU-PLGAnanoparticles inhibited the escalation of OSCC at a different time, 24, 48, 72 hours, carcinoma escalation inhibitionrate were in high level for ?-tocopherol-FU-PLGA nanoparticles (8.
0 µg/ml) inSCC-15 cells as 79.39%, 56.93% & 46.63 respectively, and comparatively lowinhibition rate 69.45%, 48.
96% & 36.28 at the time 24, 48, 72 hoursrespectively for 5-FU-PLGA NPs, the results confirmed the intense inhibition ofOSCC by ?-tocopherol-FU-PLGA nanoparticles as showing in graph of Figure 6 (A) & (B). The inhibition ratefor ?-tocopherol-FU-PLGA nanoparticles wasincreased as non-target 5-FU-PLGA NPs approx in lesser intense 45.29& 39.58% respectively for both at time 24 hrs in SCC-15, as the timeincreases the cytotoxicity effects of ?-tocopherol-FU-PLGA nanoparticles inSCC-15 was showed higher percentage of inhibition, 79.98% at time 96 hrs and confirm approximately steady stateinhibition 83.74% up to 160 hrs, as 5-FU-PLGA NPs was showed lower inhibitionrate up to 59.25% at the time 160 hrs as plotted graph in Figure 7.
